Gabbro is any of several medium- or coarse-grained rocks that consist primarily of plagioclase feldspar and pyroxene. Gabbro is dense material.

Why it’s using for concrete?

Gabbro aggregate used concrete is highest compressive and flexural tensile strength and abrasion resistance than other aggregate used concrete. Then engineers are recommending to uses gabbro aggregates for the concrete where high compressive/ tensile strength required, like piles, columns and walls.

There is a research regarding “The influence of aggregate type on the strength and abrasion resistance of high strength concrete”. According to the research Gabbro concrete showed the highest compressive and flexural tensile strength and abrasion resistance

Other uses

Ocellar varieties of gabbro can be used as ornamental facing stones, paving stones and it is also known by the trade name of 'black granite', which is a popular type of graveyard headstone used in funerary rites. It is also used in kitchens and their countertops, also under the misnomer of 'black granite'.